🐚 simple_shell

0x16. C - Simple Shell

A lightweight UNIX-style shell implemented in C—supports command execution, arguments, built-ins, and environmental variables. Ideal for learning process control, system calls, and shell fundamentals

A lightweight UNIX-style shell implemented in C—supports command execution, arguments, built-ins, and environmental variables. Ideal for learning process control, system calls, and shell fundamentals.

Learning Objectives:bulb:

What you should learn from this project:

• Who designed and implemented the original Unix operating system
• Who wrote the first version of the UNIX shell
• Who invented the B programming language (the direct predecessor to the C programming language)
• Who is Ken Thompson
• How does a shell work
• What is a pid and a ppid
• How to manipulate the environment of the current process
• What is the difference between a function and a system call
• How to create processes
• What are the three prototypes of main
• How does the shell use the PATH to find the programs
• How to execute another program with the execve system call
• How to suspend the execution of a process until one of its children terminates
• What is EOF / “end-of-file”?

0. Betty would be proud

• Write a beautiful code that passes the Betty checks

1. Simple shell 0.1

• Write a UNIX command line interpreter

2. Simple shell 0.2

• Handle command lines with arguments

3. Simple shell 0.3

• Handle the PATH

4. Simple shell 0.4

• Implement the exit built-in, that exits the shell

5. Simple shell 1.0

• Implement the env built-in, that prints the current environment

6. Simple shell 0.1.1

• Write your own getline function

7. Simple shell 0.2.1

• You are not allowed to use strtok

8. Simple shell 0.4.1

• handle arguments for the built-in exit

9. setenv, unsetenv

• Implement the setenv and unsetenv builtin commands

10. cd

• Implement the builtin command cd

11. ;

• Handle the commands separator ;

12. && and ||

• Handle the && and || shell logical operators

13. alias

• Implement the alias builtin command

14. variables

• Handle variables replacement - Handle the $? variable - Handle the $$ variable

15. comments

• Handle comments (#)

16. File as input

• Your shell can take a file as a command line argument

---